Normalizing coefficient for tanh

main.go

package main

import (
	"fmt"
	"math"

	"github.com/unixpickle/num-analysis/integration"
)

func main() {
	v := integration.Integrate(func(x float64) float64 {
		return math.Exp(-x*x/2) / math.Sqrt(2*math.Pi) * math.Pow(math.Tanh(x), 2)
	}, integration.Interval{Start: -20, End: 20})
	fmt.Println(1 / math.Sqrt(v))
}